96 BOTANICAL GAZETTE [aucusr 
The vegetation consists broadly of a higher development of the 
vegetation of the inner grass plain—the scanty turf of the hollows” 
becoming the broad expanse of meadow turf of the swales, and— 
the juniper mats extending greatly with the addition of many young — 
nn 
white spruces. So distinct are the turf of the swales and the juniper — 
mats, with their trees, from one another, that there result glades 
and vistas of park-like and charming aspect, as shown especially — 
well in jig. 8. 3 
First in importance are the juniper mats, for they inaugurate 
the woods. These mats, composed either of large radiating patches 
of this plant, or else variously united and combined with pate 
of waxberry, Hudsonia, and blueberry, extend greatly in diamete 
covering the crests as well as the slopes of the dune beaches, 
thus form a woody net in the shelter of which several other form 
mostly markedly dwarfed, gain foothold. A typical example 
shown in fig. 9. Some of the plants of the grass plain persis 
especially the beach grass, pearly everlasting, and yarrow. 1 
new forms which appear are, first of all, the common crowberry, # 
peirum nigrum, and the rock cranberry, Vaccinium Vitis-Idaea mt 
fcllowed closely by the three-toothed cinquefoil, Potentilla triden 
all of them plants characteristic of dry upland rocky situations 
Less frequent are the little gentian, Gentiana Amarella acuta, and 
the large cranberry, Vaccinium macrocarpon, plants belonging | 
moist places. And when the mats are especially well developed 
there come in, as shown in fig. g, the reindeer lichen, Cladomia — 
rangifera, and a brown moss which I take to be the Aulacomnium 
palustre (so much more highly developed in the woods), another 
curious mixture of xerophytic and hydrophytic forms. We have 
therefore upon these juniper mats a very heterogeneous assem 
blage of forms drawn from diverse natural habitats all the babs 
from rocky hills to bogs. They do not exist here, therefore, ™ 
virtue of adaptation to this position, but plainly represent thos 
forms of the flora of this region whose adaptations happen to ; 
these conditions, or whose range of physiological toleration happe* 
to be great enough to permit endurance of the conditions here. © 
these matters we shall know more in the future, but their mention 
helps to emphasize how large an element of accident or incident 
